Agrin plays a major role in the coalescence of the aquaporin-4 clusters induced by gamma-1-containing laminin

The basement membrane that seperates the endothelial cells and astrocytic endfeet that comprise the blood–brain barrier is rich in collagen, laminin, agrin, and perlecan. Previous studies have demonstrated that the proper recruitment of the water-permeable channel aquaporin-4 (AQP4) to astrocytic endfeet is dependent on interactions between laminin and the receptor dystroglycan. In this study, we conducted a deeper investigation into how the basement membrane might further regulate the expression, localization, and function of AQP4, using primary astrocytes as a model system. We found that treating these cells with laminin causes endogenous agrin to localize to the cell surface, where it co-clusters with β-dystroglycan (β-DG). Conversely, agrin sliencing profoundly disrupts β-DG clustering. As in the case of laminin111, Matrigel™, a complete basement membrane analog, also causes the clustering of AQP4 and β-DG. This clustering, whether induced by laminin111 or Matrigel™ is inhibited when the astrocytes are first incubated with an antibody against the γ1 subunit of laminin, suggesting that the latter is crucial to the process. Finally, we showed that laminin111 appears to negatively regulate AQP4-mediated water transport in astrocytes, suppressing the cell swelling that occurs following a hypoosmotic challenge. This suppression is abolished if DG expression is silenced, again demonstrating the central role of this receptor in relaying the effects of laminin.     

Genotoxicity evaluation of effluents from textile industries of the region Fez-Boulmane, Morocco: a case study

In order to investigate the biological hazard of effluents from textile industries of Fez-Boulmane region in Morocco, mutagenicity and phytotoxicity tests were performed on different biological systems. Moreover, the efficiency of a Sequencing Batch Reactor (SBR) system, working by activated sludge on a laboratory scale, was estimated by comparing the ecotoxicity results observed before and after wastewater treatment. Evaluation of the genotoxic potential was investigated by means of classic mutagenicity tests on D7 strain of Saccharomyces cerevisiae and by phytotoxicity tests on Allium sativum L., Vicia faba L. and Lactuca sativa L., estimating micronuclei presence, mitotic index and cytogenetic anomalies. The results obtained by testing untreated wastewater demonstrated major genotoxicity effects in S. cerevisiae and various levels of phytotoxicity in the three plant systems, while after SBR treatment no more ecotoxicological consequences were observed. These data confirm the effectiveness of the SBR system in removing toxic substances from textile wastewaters in Fez-Boulmane region.     

Effects of Different Adjuvants in the Context of Intramuscular and Intranasal Routes on Humoral and Cellular Immune Responses Induced by Detergent-Split A/H3N2 Influenza Vaccines in Mice

Influenza A/H3N2 viruses have caused the most severe epidemics since 1968 despite current immunization programs with inactivated vaccines. We undertook a side-by-side preclinical evaluation of different adjuvants (Alum, AS03, and Protollin) and routes of administration (intramuscular [i.m.] and intranasal [i.n.]) for assessing their effect on the immunogenicity and cross-reactivity of inactivated split vaccines (A/H3N2/New York/55/2004). Humoral and T cell-mediated immune responses against the homologous virus and a heterologous drifted strain (A/H3N2/Wisconsin/67/2005) were measured in BALB/c mice at 2, 6, and 19 weeks postboost. The AS03- and Alum-adjuvanted i.m. vaccines induced at least an 8-fold increase over the nonadjuvanted vaccine in functional antibody titers against both the homotypic and heterotypic strains and low IgG2a and high IgG1 levels, suggesting a mixed Th1/Th2 response with a Th2 trend. The Protollin-adjuvanted i.n. vaccine induced the lowest IgG1/IgG2a ratio, which is indicative of a mixed Th1/Th2-type profile with a Th1 trend. This adjuvanted vaccine was the only vaccine to stimulate a mucosal IgA response. Whatever the timing after the boost, both hemagglutination inhibition (HAI) and microneutralization (MN) titers were higher with the AS03-adjuvanted i.m. vaccine than with the protollin-adjuvanted i.n. vaccine. Finally, the Alum-adjuvanted i.m. vaccine and the lower-dose Protollin-adjuvanted i.n. vaccine elicited significantly higher CD4⁺ Th1 and Th2 responses and more gamma interferon (IFN-γ)-producing CD8⁺ T cells than the nonadjuvanted vaccine. Our data indicate that the adjuvanted vaccines tested in this study can elicit stronger, more persistent, and broader immune responses against A/H3N2 strains than nonadjuvanted inactivated influenza vaccines.     

Auriculoventricular blocks in the acute phase of myocardial infarction. Course and prognosis. Apropos of 90 cases

The objective is to study the clinical and electrocardiographic characteristics as well as the course of myocardial infarction complicated by atrio-ventricular block (AVB), and to propose a management to acute myocardial infarction with A-V block. This study concerns 90 patients (78 men and 12 women), with a mean age of 58 years. The overall frequency of AVB is 7.6 p. cent. The infarction is most of the time found posteriorly (51 p. cent of the cases). Syncopes are essentially seen in complete AVB (81 p. cent) and with deep antero-septal necrosis (73 p. cent). Heart failure is especially the complication of anterior (73 p. cent) and deep septal (78 p. cent) necrosis. The mortality of myocardial infarction complicated by A-V block (41 p. cent) is higher than that of uncomplicated necroses (15 p. cent). The prognosis is usually favorable in posteriorly located infarctions where the A-V block is usually regressive and benign while it is much more severe in other locations where the conduction disorders associated with severe myocardial lesions. Temporary and/or permanent electrosystolic stimulation must be well codified in its indications which should be broadened, especially in case of anterior or deep septal necrosis.     

Prenatal exposure to diazinon induced developmental impairments in rat offspring: Behavioral and biochemical aspects

Prenatal acute and chronic exposure to organophosphorus pesticides may evoke physical and behavioral impairments in offspring development. In this report, pregnant Wistar rats were intraperitoneally treated with diazinon (DZN) (10 mg/kg b.w) from G7 to G14 of pregnancy. The animals (males and females) were randomly chosen from the litters. They were observed afterwards for physical (body weight change, incisor eruption and eye opening), neuromotor and behavioral development (surface righting reflex, palmar grasp reflex, negative geotaxis, forelimb support test, open field test and Morris water maze) and brain acetylcholinesterase activity was measured. The Results showed differences in physical and neuromotor parameters and brain acetylcholinesterase activity between treated and control groups. At the adolescence period, the open field test showed hyperactivity, as well as an enhancement of an exploratory state associated with anxiolytic­like effect. The Morris water maze showed an enhancement of spatial memory. We conclude that DZN at high doses was able to disrupt physical and neuromotor development in pups during lactation and also modify behavioral and cognitive state at adolescence period. This may have been linked with organophosphorus mediated inhibition of central nervous system acetylcholinesterase activity.